<?php // $Id: move_updown_field.class.php,v 1.4 2007/10/10 05:25:21 nicolasconnault Exp $

///////////////////////////////////////////////////////////////////////////
//																	   //
// NOTICE OF COPYRIGHT												   //
//																	   //
// Moodle - Modular Object-Oriented Dynamic Learning Environment		 //
//		  http://moodle.com											//
//																	   //
// Copyright (C) 1999 onwards Martin Dougiamas		http://dougiamas.com  //
//		   (C) 2001-3001 Eloy Lafuente (stronk7) http://contiento.com  //
//																	   //
// This program is free software; you can redistribute it and/or modify  //
// it under the terms of the GNU General Public License as published by  //
// the Free Software Foundation; either version 2 of the License, or	 //
// (at your option) any later version.								   //
//																	   //
// This program is distributed in the hope that it will be useful,	   //
// but WITHOUT ANY WARRANTY; without even the implied warranty of		//
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the		 //
// GNU General Public License for more details:						  //
//																	   //
//		  http://www.gnu.org/copyleft/gpl.html						 //
//																	   //
///////////////////////////////////////////////////////////////////////////

/// This class will will move one field up/down

class move_updown_field extends XMLDBAction {

	/**
	 * Init method, every subclass will have its own
	 */
	function init() {
		parent::init();

	/// Set own custom attributes

	/// Get needed strings
		$this->loadStrings(array(
		/// 'key' => 'module',
		));
	}

	/**
	 * Invoke method, every class will have its own
	 * returns true/false on completion, setting both
	 * errormsg and output as necessary
	 */
	function invoke() {
		parent::invoke();

		$result = true;

	/// Set own core attributes
		$this->does_generate = ACTION_NONE;
		//$this->does_generate = ACTION_GENERATE_HTML;

	/// These are always here
		global $CFG, $XMLDB;

	/// Do the job, setting result as needed
	/// Get the dir containing the file
		$dirpath = required_param('dir', PARAM_PATH);
		$dirpath = $CFG->dirroot . stripslashes_safe($dirpath);

	/// Get the correct dirs
		if (!empty($XMLDB->dbdirs)) {
			$dbdir =& $XMLDB->dbdirs[$dirpath];
		} else {
			return false;
		}
		if (!empty($XMLDB->editeddirs)) {
			$editeddir =& $XMLDB->editeddirs[$dirpath];
			$structure =& $editeddir->xml_file->getStructure();
		}
	/// ADD YOUR CODE HERE
		$prev = NULL;
		$next = NULL;
		$tableparam = required_param('table', PARAM_CLEAN);
		$fieldparam = required_param('field', PARAM_CLEAN);
		$direction  = required_param('direction', PARAM_ALPHA);
		$tables =& $structure->getTables();
		$table =& $structure->getTable($tableparam);
		$fields =& $table->getFields();
		if ($direction == 'down') {
			$field  =& $table->getField($fieldparam);
			$swap   =& $table->getField($field->getNext());
		} else {
			$swap   =& $table->getField($fieldparam);
			$field  =& $table->getField($swap->getPrevious());
		}

	/// Change the field before the pair
		if ($field->getPrevious()) {
			$prev =& $table->getField($field->getPrevious());
			$prev->setNext($swap->getName());
			$swap->setPrevious($prev->getName());
			$prev->setChanged(true);
		} else {
			$swap->setPrevious(NULL);
		}
	/// Change the field after the pair
		if ($swap->getNext()) {
			$next =& $table->getField($swap->getNext());
			$next->setPrevious($field->getName());
			$field->setNext($next->getName());
			$next->setChanged(true);
		} else {
			$field->setNext(NULL);
		}
	/// Swap the fields
		$field->setPrevious($swap->getName());
		$swap->setNext($field->getName());

	/// Mark fields as changed
		$field->setChanged(true);
		$swap->setChanged(true);

	/// Table has changed
		$table->setChanged(true);

	/// Reorder the fields
		$table->orderFields($fields);

	/// Recalculate the hash
		$structure->calculateHash(true);

	/// If the hash has changed from the original one, change the version
	/// and mark the structure as changed
		$origstructure =& $dbdir->xml_file->getStructure();
		if ($structure->getHash() != $origstructure->getHash()) {
			$structure->setVersion(userdate(time(), '%Y%m%d', 99, false));
			$structure->setChanged(true);
		}

	/// Launch postaction if exists (leave this here!)
		if ($this->getPostAction() && $result) {
			return $this->launch($this->getPostAction());
		}

	/// Return ok if arrived here
		return $result;
	}
}
?>
